Intersection weld seam curve fitting based on NURBS

In the industrial application of intersecting line welding, the planning of welding paths directly affects welding quality and efficiency. Currently, many robotic welding path planning processes rely on manual programming, which makes it challenging to handle complex curved seams or multiple intersecting lines in structures. For intricate structural components, welding robots must avoid collisions with the base material and ensure that the welding torch can reach every seam location. Optimized path planning can reduce dead zones and enhance the robot’s operational capabilities in confined spaces. This paper proposes a curve fitting method based on Non-Uniform Rational B-Splines (NURBS), utilizing discrete welding point data obtained from the mathematical model of the intersecting lines. An adaptive threshold strategy for handling outliers is introduced, followed by fitting the data points using NURBS curves.